The brittleness in steel at elevated temperature is ______

Brittleness in steel at elevated temperatures is referred to as "red shortness." This condition occurs when steel becomes brittle and loses ductility when heated, especially when it contains impurities such as phosphorus. At elevated temperatures, particularly those where steel might be processed, the steel can fracture easily rather than deform, making it "red short."

The term specifically describes the degradation of material properties due to the presence of certain elements in the steel matrix, and it's particularly pertinent in applications involving hot working processes. Understanding red shortness is crucial for metallurgists and engineers when selecting materials for high-temperature environments, as it directly impacts the performance and safety of the steel in various applications.

In contrast, hard drawn refers to a cold processing method that increases strength but does not inherently relate to brittleness at high temperatures. Cold lap refers to a defect in welding or metal joining, which is unrelated to the properties of steel when heated. Residual stresses are internal stresses that remain in a material after the original cause of the stresses has been removed; while they can affect performance, they do not specifically categorize the brittleness of steel at elevated temperatures in the same direct manner as red shortness.